I think you're referring to Hauptwerk's 'piston toolbars', the first one of which is docked at the bottom of the primary screen for each organ by default.

If you've accidentally closed that toolbar, you can open it again using 'View | Piston toolbars (for this organ) | Main console window piston toolbar'. The 'Control panels and piston toolbars' section in the main Hauptwerk user guide (on the Help menu in Hauptwerk; pages 59-65 in the current v4.2.1 version) has full details on how to use them, including opening/closing, moving/docking, and changing their size/orientation to your preferences.

Best regards,Martin.

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